Re: [PATCH v4 1/2] target/arm: Increase MAX_PACKET_LENGTH for SME ZA remote gdb debugging

["Alex Bennée" <alex.bennee@linaro.org>]

Vacha Bhavsar <vacha.bhavsar@oss.qualcomm.com> writes:

> This patch increases the value of the MAX_PACKET_LEGNTH to
> 131100 from 4096 to allow the GDBState.line_buf to be large enough
> to accommodate the full contents of the SME ZA storage when the
> vector length is maximal. This is in preparation for a related
> patch that allows SME register visibility through remote GDB
> debugging.
>
> Signed-off-by: Vacha Bhavsar <vacha.bhavsar@oss.qualcomm.com>
> ---
> Changes since v3:
> - this patch was not present in version 3
>
>  gdbstub/internals.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/gdbstub/internals.h b/gdbstub/internals.h
> index bf5a5c6302..b58a66c201 100644
> --- a/gdbstub/internals.h
> +++ b/gdbstub/internals.h
> @@ -11,7 +11,7 @@
>  
>  #include "exec/cpu-common.h"
>  
> -#define MAX_PACKET_LENGTH 4096
> +#define MAX_PACKET_LENGTH 131100

This is a rather large expansion for something that ends up in a static at:

    char line_buf[MAX_PACKET_LENGTH];

I think maybe its time to get rid of this hardcoded define and make line_buf a
dynamically re-sizeable buffer along the lines of str_buf and mem_buf.
In fact make it a GString and we can get rid of line_buf_index as well.

>  
>  /*
>   * Shared structures and definitions

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro